Switch handle for field assembly

ABSTRACT

An elongated lever-type handle attachable to a switch in the field or after the switch is otherwise completely fabricated has a substantially cylindrical axial recess with an interior cylindrical bead. A switch-operating lever has a cylindrical part adapted to enter the handle recess, and a peripheral groove in which the bead seats. The outer end of the lever is tapered to facilitate sliding of the handle on the lever, and the inner end of the lever is flared and engaged by the end of the handle to afford a tight fit. Key-and-slot means on the lever and handle prevent relative rotation in engaged position.

United States Patent John J. Dennison Southington, Conn. 49,449

June 24, 1970 Nov. 2, 197 l Arrow-Hart, Inc. Hartford, Conn.

Inventor Appl. No. Filed Patented Assignee SWITCH HANDLE FOR I IELD ASSEMBLY 9 Claims, 3 Drawing Figs.

References Cited UNITED STATES PATENTS 8/1965 Poulton, Jr, 200/172 A 3,175,420 3/1965 Craig 200/172AX 2,807,692 9/1957 Leslie 200/172 FOREIGN PATENTS 21,609 6/1965 Japan ZOO/l 72 A Primary Examiner-H. 0. Jones Attorney- Davis, Hoxie, Faithful] & Hapgood ABSTRACT: An elongated lever-type handle attachable to a switch in the field or after the switch is otherwise completely fabricated has a substantially cylindrical axial recess with an interior cylindrical bead. A switch-operating lever has a cylindrical part adapted to enter the handle recess, and a peripheral groove in which the bead seats. The outer end of the lever is tapered to facilitate sliding of the handle on the lever, and the inner end of the lever is flared and engaged by the end of the handle to afford a tight fit. Key-and-slot means on the lever and handle prevent relative rotation in engaged position.

SWITCH HANDLE FOR FIELD ASSEMBLY This invention relates to handles for electric switches, and, more particularly, to handles attachable and replaceable in the field, readily, by the user.

PRIOR ART in the art of electrical switching, manufacturers have provided electrical switch mechanisms which were complete with the exception of the actuating lever. The levers for such switches were commonly supplied in bulk in various colors.

This. practice provided great flexibility for the consumer in that the switch levers could be color coded for function or to provide a decorative appearance to a panel in which the,

DESCRIPTION OF THE INVENTION It is an objective of this invention to provide a switch adapted for field assembly of a handle thereto, wherein the handle can only be removed after assembly with great difficulty.

It is a further objective of this invention to provide a detachable actuating lever or handle for a switch which is easily assembled, yet provides a fastening of sufficient rigidity to give the handle a feeling of firmness.

To accomplish the purposes of this invention, a casing containing a switch mechanism has a cylindrical lever-type mounting member extending outwardly in the place of the usual operating lever or handle. An actuating lever, cylindrically recessed at one end, may be slipped onto the mounting member. The mounting member and cooperating switch handle are constructed to provide a locking engagement which effectively prevents removal of the operating handle and insures a snug fit which is relatively rigid in use. As an additional feature, means are provided to preventrotation of the operating lever on the mounting post.

FIG. 1 is a side elevation view partly in section of a switch embodying the handle invention.

FIG. 2 is a view of the actuating member of handle, partly in longitudinal section and partly broken away.

F IG. 3 is a side elevation view of the mounting member for the handle, apart from the switch. 1

Referring to the drawing, the invention is shown as applied to a conventional lever-operated switch housed in an insulation casing 10. Since the invention is useful in connection with any lever-operated switch regardless of its particular contactmoving mechanism the internal structure need not be described. 1

For the purpose of description, the invention is shown as applied to a pivoted switch-operating lever designated generally by numeral 12. in the example illustrated, the lever has an enlarged semispherical inner end 14 located within a hollow cylindrical neck 16 which is externally threaded and is secured on the casing 10, thus providing conventional means to mount the switch on a panel or elsewhere. The lever 12 pivots on an axis afforded by a radially positioned pivot pin 18, as usual in the neck 16. All the foregoing, being conventional. will be readily understood by those skilled in the art without elabration.

The lever 12 has a cylindrical end 20 extending from the part 14 outwardly from the neck 16. Near the extremity of the extension is an annular groove 22; and the circular edge or corner of the extremity is rounded as at 24 to facilitate the sliding over it of the hollow end of an actuating member or handle designated generally by numeral 30 as hereinafter described more fully. The edge of the groove 22 nearest said extremity extends radially inward forming a shoulder 23. For ready manual attachment to the lever 12, the handle 30 has a hollow cylindrical axially extending recess 32 or socket in one end of the approximately sameintemal diameter as the external diameter of the lever 12 so that handle 30 can be slid upon the lever 20 with close sliding fit.

To ensure retention of the handle 30 on the lever 12, an annular bead 34, semicircular in cross section, is formed on the wall of the recess 32 near its inner end in position to fit into the annular groove 22 of the lever when the handle 30 is slid upon the lever 12. The sharp edge or corner of the shoulder 23 will engage the bead 34 at its point of intersection with the cylindrical wall inwardly of the bead. The end of the lever 12 within therecess 32 may be shaped to conform to the shape of the inner end of the recess 32 and to abut the inner end of the recess to hold the bead against the shoulder in the manner described, without the opposite edge of the bead binding against the opposite side of the groove.

To prevent rotation of the handle on the lever 12, one or more keys 19 are formed on the lever 12 extending radially outward from the lever 12 at its base 15 in position to be received in complementary keyways 31 in the adjacent edge of the handle when it has been slipped over the lever 12.

The portion 17 of the lever 12 adjacent the base part 15 may be flared or outwardly tapered toward the base 15 just sufficiently to ensure firm engagement of the lever with the handle in that area. This prevents wobbling of the handle on the lever at that end, while the other end is held by the bead and groove and, if desired, also by the engagement of the end of the lever with the complementarily shaped end of the recess.

To afiord a finger grip part, the end of handle 30 that is opposite to its recessed end is extended. This finger grip part may be flattened, oval, cylindrical or of any other desired crosssectional shape.

In its assembled condition, the handle 30 fits over the lever 12 as shown generally in FIG. 1 with the bead 34 substantially filling the annular groove 22 and with the end of the handle engaging the tapered base 17 of the lever 12 and with the key 19 and 'keyway 31 in engagement.

The mating engagement of the bead and groove prevent removal of the handle because of the relatively great forces required to deform the ring and groove members to thepoint that they will slip relative to one another. Specifically, the sharp corner on the lever groove engages the corner formed at the point where the bead intersects the cylindrical wall of the recess 32. v

The handle and lever members may be conveniently molded from any suitable plastic insulation material, such as Derlrin (TM), a product of the DuPont Company. Other materials which combine the qualities of elasticity and self-lubrication may also be used. The property of elasticity is required to permit deformation of the handle to enable the head 34 to slip over the end 20 of the lever 12. The elasticity of the material is also desirable to insure a tight fit between the tapered base portion of the lever 12 and the recessed end of the handle 30. The property of self-lubrication is desirable to enable assembly of the handles to the switches with a minimum of effort.

It will be understood by those skilled in the art that in addition to the embodiment shown the invention may be practiced in other modifications. Specifically, the bead 34 may be formed on the lever 12 while its cooperating groove 22 may be formed in the wall of the recess 32. In that event, it might be desirable to taper the recess 32 to permit easy attachment of the handle to the lever. Also, the relative positions of the keyway and the key may be reversed.

What is claimed is:

1. In an electric switch, a pivoted operating member having a pivot portion and a lever portion, in combination with an elongated handle member adapted to be affixed to said operating member after assembly of the switch, said lever portion and said handle member having coaxial longitudinal axes,

said handle member having a recess received and slidably fitted upon said lever portion, an annular groove on one of said members and an annular bead on the other of said members engageable in said groove when said members are slid together, said groove having a surface extending perpendicularly with respect to said axes forming a corner that is rectangular in cross section, said head forming a substantially rectangular comer with the longitudinal surface adjacent thereto and engaging the first-mentioned comer, at least one of said members being formed of resilient semirigid material permitting deformation as said bead and groove are forced into engagement, the engagement of said corners preventing disengagement of said members by exercise of normal manipulative force incident to operation of the switch.

2. The combination as claimed in claim 1 wherein the cross section of said lever portion gradually increases adjacent its junction with said pivot portion and is engaged by said handle member.

3. The combination as claimed in claim 1 having key means on one of said members preventing its rotation about the longitudinal axis of the other.

4. The combination as claimed in claim I wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same 5. The combination as claimed in claim 2 having key means on one of said members preventing its rotation about the longitudinal axis of the other.

6. The combination as claimed in claim 5 wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same.

7. The combination as claimed in claim 3 wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same.

8. In an electric switch, a pivoted operating member having a pivot portion and a lever portion, in combination with an elongated handle member adapted to be affixed to said operating member after assembly of the switch, said lever portion having an annular groove along its length, said groove having a surface extending perpendicularly with respect to the axis of said lever portion forming a comer which is rectangular in cross section, said handle member having a longitudinal axis coaxial with the longitudinal axis of said lever portion and having a recess received and slidably fitted upon said lever portion, said recess having an annular head in the wall thereof in position to be received in said groove, said bead forming a comer substantially rectangular in cro section where it joins the wall of said recess and engaging the first-mentioned comer, at least one of said members being formed of resilient semirigid material and permitting deformation as said bead and groove are forced into engagement.

9. The combination as claimed in claim 8 wherein the crosssectional area of the end of said lever portion is reduced to facilitate distortion of said bead during assembly of said handle member on said operating member. 

1. In an electric switch, a pivoted operating member having a pivot portion and a lever portion, in combination with an elongated handle member adapted to be affixed to said operating member after assembly of the switch, said lever portion and said handle member having coaxial longitudinal axes, said handle member having a recess received and slidably fitted upon said lever portion, an annular groove on one of said members and an annular bead on the other of said members engageable in said groove when said members are slid together, said groove having a surface extending perpendicularly with respect to said axes forming a corner that is rectangular in cross section, said bead forming a substantially rectangular corner with the longitudinal surface adjacent thereto and engaging the first-mentioned corner, at least one of said members being formed of resilient semirigid material permitting deformation as said bead and groove are forced into engagement, the engagement of said corners preventing disengagement of said members by exercise of normal manipulative force incident to operation of the switch.
 2. The combination as claimed in claim 1 wherein the cross section of said lever portion gradually increases adjacent its junction with said pivot portion and is engaged by said handle member.
 3. The combination as claimed in claim 1 having key means on one of said members preventing its rotation about the longitudinal axis of the other.
 4. The combination as claimed in claim 1 wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same.
 5. The combination as claimed in claim 2 having key means on one of said members preventing its rotation about the longitudinal axis of the other.
 6. The combination as claimed in claim 5 wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same.
 7. The combination as claimed in claim 3 wherein the end of said lever portion has a shape complementary to the inner end of said recess and engages the same.
 8. In an electric switch, a pivoted operating member having a pivot portion and a lever portion, in combination with an elongated handle member adapted to be affixed to said operating member after assembly of the switch, said lever portion having an annular groove along its length, said groove having a surface extending perpendicularly with respect to the axis of said lever portion forming a corner which is rectangular in cross section, said handle member having a longitudinal axis coaxial with the longitudinal axis of said lever portion and having a recess received and slidably fitted upon said lever portion, said recess having an annular bead in the wall thereof in position to be received in said groove, said bead forming a corner substantially rectangular in cross section where it joins the wall of said recess and engaging the first-mentioned corner, at least one of said members being formed of resilient semirigid material and permitting deformation as said bead and groove are forced into engagement.
 9. The combination as claimed in claim 8 wherein the cross-sectional area of the end of said lever portion is reduced to facilitaTe distortion of said bead during assembly of said handle member on said operating member. 